From: Frans Pop <elendil@planet.nl>
To: Sean MacLennan <smaclennan@pikatech.com>
Cc: linuxppc-dev@ozlabs.org, Pekka Enberg <penberg@cs.helsinki.fi>,
Paul Mackerras <paulus@samba.org>,
linux-kernel@vger.kernel.org,
David Gibson <david@gibson.dropbear.id.au>
Subject: Re: Badness on the Warp
Date: Sun, 21 Jun 2009 06:28:33 +0200 [thread overview]
Message-ID: <200906210628.35553.elendil@planet.nl> (raw)
In-Reply-To: <20090620194250.5a3e826f@lappy.seanm.ca>
On Sunday 21 June 2009, Sean MacLennan wrote:
> I found the source of the badness. The backtrace is correct:
>
> uic_init_one
So that's in arch/powerpc/sysdev/uic.c.
> ___alloc_bootmem
> ___alloc_bootmem_nopanic
> alloc_arch_preferred_bootmem
>
> In alloc_arch_preferred_bootmem we have:
>
> if (WARN_ON_ONCE(slab_is_available()))
> return kzalloc(size, GFP_NOWAIT);
>
> Since the slab is available (it had better be or the call will return
> NULL), we get the badness message, then a successful return from
> kzalloc.
>
> I believe the author wants something like:
>
> if (slab_is_available())
> return kzalloc(size, GFP_NOWAIT);
> else
> WARN_ON_ONCE(1);
Well, I myself have no idea. It could also indicate a bug in the uic code.
But let's CC some people responsible for this code. Pekka recently added
this WARN that triggers in your case; David and Paul look to be the
people most involved in the uic code.
Start of the thread is at http://lkml.org/lkml/2009/6/20/165.
Cheers,
FJP
WARNING: multiple messages have this Message-ID (diff)
From: Frans Pop <elendil@planet.nl>
To: Sean MacLennan <smaclennan@pikatech.com>
Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org,
Pekka Enberg <penberg@cs.helsinki.fi>,
David Gibson <david@gibson.dropbear.id.au>,
Paul Mackerras <paulus@samba.org>
Subject: Re: Badness on the Warp
Date: Sun, 21 Jun 2009 06:28:33 +0200 [thread overview]
Message-ID: <200906210628.35553.elendil@planet.nl> (raw)
In-Reply-To: <20090620194250.5a3e826f@lappy.seanm.ca>
On Sunday 21 June 2009, Sean MacLennan wrote:
> I found the source of the badness. The backtrace is correct:
>
> uic_init_one
So that's in arch/powerpc/sysdev/uic.c.
> ___alloc_bootmem
> ___alloc_bootmem_nopanic
> alloc_arch_preferred_bootmem
>
> In alloc_arch_preferred_bootmem we have:
>
> if (WARN_ON_ONCE(slab_is_available()))
> return kzalloc(size, GFP_NOWAIT);
>
> Since the slab is available (it had better be or the call will return
> NULL), we get the badness message, then a successful return from
> kzalloc.
>
> I believe the author wants something like:
>
> if (slab_is_available())
> return kzalloc(size, GFP_NOWAIT);
> else
> WARN_ON_ONCE(1);
Well, I myself have no idea. It could also indicate a bug in the uic code.
But let's CC some people responsible for this code. Pekka recently added
this WARN that triggers in your case; David and Paul look to be the
people most involved in the uic code.
Start of the thread is at http://lkml.org/lkml/2009/6/20/165.
Cheers,
FJP
next prev parent reply other threads:[~2009-06-21 4:28 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-06-20 19:48 Badness on the Warp Sean MacLennan
2009-06-20 20:56 ` Frans Pop
2009-06-20 20:56 ` Frans Pop
2009-06-20 23:10 ` Sean MacLennan
2009-06-20 23:26 ` Frans Pop
2009-06-21 4:08 ` Daniel Barkalow
2009-06-21 4:08 ` Daniel Barkalow
2009-06-20 23:42 ` Sean MacLennan
2009-06-21 4:28 ` Frans Pop [this message]
2009-06-21 4:28 ` Frans Pop
2009-06-21 10:20 ` Pekka Enberg
2009-06-21 10:20 ` Pekka Enberg
2009-06-21 22:25 ` Benjamin Herrenschmidt
2009-06-21 22:25 ` Benjamin Herrenschmidt
2009-06-21 22:36 ` Sean MacLennan
2009-06-21 22:36 ` Sean MacLennan
2009-06-21 22:57 ` Benjamin Herrenschmidt
2009-06-21 22:57 ` Benjamin Herrenschmidt
2009-06-22 4:48 ` Pekka Enberg
2009-06-22 4:48 ` Pekka Enberg
2009-06-23 5:24 ` Sean MacLennan
2009-06-23 5:24 ` Sean MacLennan
2009-06-21 7:03 ` H. Peter Anvin
2009-06-21 7:03 ` H. Peter Anvin
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